Porphyria laboratory diagnosis

Minder El, Schneider-Yin X (2002) The porphyrias. In Blau N, Duran M, Blaskovics ME, Gibson KM (eds) Physician s Guide to The Laboratory Diagnosis of Metabolic Diseases. Springer, Berlin, Heidelberg, New York, pp 593-613... 

The diagnosis of a specific type of porphyria can generally be established by consideration of the chnical and family history, the physical examination, and appropriate laboratory tests. The major findings in the six principal types of porphyria are listed in Table 32-2. 

The clinical features of the porphyrias are insufficiently specific to enable then diagnosis without laboratory investigation. In patients with current symptoms caused by porphyria, it is always possible to demonstrate excessive production of heme precursors. Diagnosis depends on demonstrating specific patterns of overproduction of heme precursors (Table 32-5) and is usually straightforward provided appropriate specimens are examined for the relevant intermediates using adequately sensitive techniques,... 

Sometimes the laboratory is asked to make a retrospective diagnosis of porphyria after the patient has ftiUy recovered from an attack or as the cause of a chronic neuropsychiatric disorder some time after the onset of the illness. The first step is to quantify urinary PEG screening tests are too insensitive for this purpose. Fecal porphyrin is measured... 

Blake D, Poulos V, Rossi R. Diagnosis of porphyria— recommended methods for peripheral laboratories. Clinical Biochemical Reviews 1992 13(suppl l) Sl-24. 

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